Ambient Particle Components and Newborn Blood Pressure in Project Viva

Precipitation and Adolescent Respiratory Health in the Northeast United States

Rationale: With more frequent and intense precipitation events across the globe due to a changing climate, there is a need to understand the relationship between precipitation and respiratory health. Precipitation may trigger asthma exacerbations, but little is known about how precipitation affects lung function and airway inflammation in early adolescents. Objectives: To determine if short-term precipitation exposure is associated with lung function and airway inflammation in early adolescents and if ever having a diagnosis of asthma modifies associations of precipitation with lung function and airway inflammation. Methods: In a prospective prebirth cohort, Project Viva, that included 1,019 early adolescents born in the northeastern United States, we evaluated associations of 1-, 2-, 3-, and 7-day moving averages of precipitation in the preceding week and forced expiratory volume in 1 second, forced vital capacity, and fractional exhaled nitric oxide (FeNO) using linear regression. We used log-transformed FeNO with effect estimates presented as percentage change. We adjusted for maternal education and household income at enrollment; any smoking in the home in early adolescence; child sex, race/ethnicity, and ever asthma diagnosis; and age, height, weight, date, and season (as sine and cosine functions of visit date) at the early adolescent visit and moving averages for mean daily temperature (same time window as exposure). Results: In fully adjusted linear models, 3- and 7-day moving averages for precipitation were positively associated with FeNO but not lung function. Every 2-mm increase in the 7-day moving average for precipitation was associated with a 4.0% (95% confidence interval, 1.1, 6.9) higher FeNO. There was evidence of effect modification by asthma status: Precipitation was associated with lower forced vital capacity and higher FeNO among adolescents with asthma. We also found that outdoor aeroallergen sensitization (immunoglobulin E against common ragweed, oak, ryegrass, or silver birch) modified associations of precipitation with FeNO, with higher FeNO in sensitized adolescents compared with nonsensitized adolescents. The associations of precipitation with FeNO were not explained by relative humidity or air pollution exposure. Conclusions: We found that greater short-term precipitation may trigger airway inflammation in adolescents, particularly among those with asthma.

Pre- and postnatal particulate matter exposure and blood pressure in children and adolescents: A systematic review and meta-analysis

BACKGROUND

Early life is a susceptible period of air pollution-related adverse health effects. Hypertension in children might be life-threatening without prevention or treatment. Nevertheless, the causative association between environmental factors and childhood hypertension was limited. In the light of particulate matter (PM) as an environmental risk factor for cardiovascular diseases, this study investigated the association of pre- and postnatal PM exposure with blood pressure (BP) and hypertension among children and adolescents.

METHOD

Four electronic databases were searched for related epidemiological studies published up to September 13, 2022. Stata 14.0 was applied to examine the heterogeneity among the studies and evaluate the combined effect sizes per 10 μg/m³ increase of PM by selecting the corresponding models. Besides, subgroup analysis, sensitivity analysis, and publication bias test were also conducted.

RESULTS

Prenatal PM_2.5 exposure was correlated with increased diastolic blood pressure (DBP) in offspring [1.14 mmHg (95% CI: 0.12, 2.17)]. For short-term postnatal exposure effects, PM_2.5 (7-day average) was significantly associated with systolic blood pressure (SBP) [0.20 mmHg (95% CI: 0.16, 0.23)] and DBP [0.49 mmHg (95% CI: 0.45, 0.53)]; and also, PM₁₀ (7-day average) was significantly associated with SBP [0.14 mmHg (95% CI: 0.12, 0.16)]. For long-term postnatal exposure effects, positive associations were manifested in SBP with PM_2.5 [β = 0.44, 95% CI: 0.40, 0.48] and PM₁₀ [β = 0.35, 95% CI: 0.19, 0.51]; DBP with PM₁ [β = 0.45, 95% CI: 0.42, 0.49], PM_2.5 [β = 0.31, 95% CI: 0.27, 0.35] and PM₁₀ [β = 0.32, 95% CI: 0.19, 0.45]; and hypertension with PM₁ [OR = 1.43, 95% CI: 1.40, 1.46], PM_2.5 [OR = 1.65, 95% CI: 1.29, 2.11] and PM₁₀ [OR = 1.26, 95% CI: 1.09, 1.45].

CONCLUSION

Both prenatal and postnatal exposure to PM can increase BP, contributing to a higher prevalence of hypertension in children and adolescents.

The pathophysiological and molecular mechanisms of atmospheric PM2.5 affecting cardiovascular health: A review

BACKGROUND

Exposure to ambient fine particulate matter (PM2.5, with aerodynamic diameter less than 2.5 µm) is a leading environmental risk factor for global cardiovascular health concern.

OBJECTIVE

To provide a roadmap for those new to this field, we reviewed the new insights into the pathophysiological and cellular/molecular mechanisms of PM2.5 responsible for cardiovascular health.

MAIN FINDINGS

PM2.5 is able to disrupt multiple physiological barriers integrity and translocate into the systemic circulation and get access to a range of secondary target organs. An ever-growing body of epidemiological and controlled exposure studies has evidenced a causal relationship between PM2.5 exposure and cardiovascular morbidity and mortality. A variety of cellular and molecular biology mechanisms responsible for the detrimental cardiovascular outcomes attributable to PM2.5 exposure have been described, including metabolic activation, oxidative stress, genotoxicity, inflammation, dysregulation of Ca2+ signaling, disturbance of autophagy, and induction of apoptosis, by which PM2.5 exposure impacts the functions and fates of multiple target cells in cardiovascular system or related organs and further alters a series of pathophysiological processes, such as cardiac autonomic nervous system imbalance, increasing blood pressure, metabolic disorder, accelerated atherosclerosis and plaque vulnerability, platelet aggregation and thrombosis, and disruption in cardiac structure and function, ultimately leading to cardiovascular events and death. Therein, oxidative stress and inflammation were suggested to play pivotal roles in those pathophysiological processes.

CONCLUSION

Those biology mechanisms have deepen insights into the etiology, course, prevention and treatment of this public health concern, although the underlying mechanisms have not yet been entirely clarified.

Associations between plasma metal mixture exposure and risk of hypertension: A cross-sectional study among adults in Shenzhen, China

Background

Metal exposure affects human health. Current studies mainly focus on the individual health effect of metal exposure on hypertension (HTN), and the results remain controversial. Moreover, the studies assessing overall effect of metal mixtures on hypertension risk are limited.

Methods

A cross-sectional study was conducted by recruiting 1,546 Chinese adults who attended routine medical check-ups at the Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen. The plasma levels of 13 metals were measured using inductively coupled plasma mass spectrometry. Multivariate logistic regression model, restricted cubic spline (RCS) model and the Bayesian Kernel Machine Regression (BKMR) model were applied to explore the single and combined effect of metals on the risk of HTN.

Results

A total of 642 (41.5%) participants were diagnosed with HTN. In the logistic regression model, the adjusted odds ratios (ORs) were 0.71 (0.52, 0.97) for cobalt, 1.40 (1.04, 1.89) for calcium, 0.66 (0.48, 0.90), and 0.60 (0.43, 0.83) for aluminum in the second and third quartile, respectively. The RCS analysis showed a V-shaped or an inverse V-shaped dose-response relationship between metals (aluminum or calcium, respectively) and the risk of HTN (P for non-linearity was 0.017 or 0.009, respectively). However, no combined effect was found between metal mixture and the risk of hypertension.

Conclusions

Plasma levels of cobalt, aluminum and calcium were found to be associated with the risk of HTN. Further studies are needed to confirm our findings and their potential mechanisms with prospective studies and experimental study designs.

Perinatal Metal and Metalloid Exposures and Offspring Cardiovascular Health Risk

PURPOSE OF REVIEW

Toxic metal exposures have been associated with cardiovascular disease in adults and growing evidence suggests metal exposures also adversely affect cardiovascular phenotypes in childhood and adolescence. However, to our knowledge, the influence of perinatal metals exposure, particularly metal mixtures, in relation to cardiovascular-related outcomes have not been comprehensively reviewed.

RECENT FINDINGS

We summarized 17 contemporary studies (2017-2021) that investigated the impact of perinatal metal exposures on measures of cardiovascular health in children. Accumulating evidence supports a potential adverse impact of perinatal Pb exposure on BP in children. Fewer recent studies have focused on perinatal As, Hg, and Cd; thus, the cardiovascular impacts of these metals are less clear. Studies of metal mixtures demonstrate that interactions between metals may be complex and have identified numerous understudied elements and essential metals, including Mo, Co, Ni, Se, Zn, and Mn, which may influence cardiovascular risk. A key question that remains is whether perinatal metals exposure influences cardiovascular health into adulthood. Comparisons across studies remain challenging due to several factors, including differences in the timing of exposure/outcome assessments and exposure biomarkers, as well as variability in exposure levels and mixture compositions across populations. Future studies longitudinally investigating trajectories of cardiovascular outcomes could help determine the influence of perinatal metals exposure on long-term effects of clinical relevance in later life and whether interventions, which reduce metals exposures during this key developmental window, could alter disease development.

Exposure to metal mixtures and hypertensive disorders of pregnancy: A nested case-control study in China

Exposure to metals has been linked with the risk of hypertensive disorders of pregnancy (HDP), but little is known about the potential effects of exposure to metal mixtures. Thus, our study aimed to investigated the impact of a complex mixture of metals on HDP, especially the interactions among metal mixtures. We did a population-based nested case-control study from October 2013 to October 2016 in Wuhan, China, including 146 HDP cases and 292 controls. Plasma concentrations of Aluminum (Al), Barium (Ba), Cobalt (Co), Copper (Cu), Lead (Pb), Mercury (Hg), Molybdenum (Mo), Nickel (Ni), Selenium (Se), Strontium (Sr), Thallium (Tl), and Vanadium (V) were measured and collected between 10 and 16 gestational weeks. We employed quantile g-computation, conditional logistic regression models, and Bayesian Kernel Machine Regression (BKMR) to assess the association of individual metals and metal mixtures with HDP risk. In the quantile g-computation, the OR for a joint tertile increase in plasma concentrations was 3.67 (95% CI: 1.70, 7.91). Hg contributed the largest positive weights and followed by Al, Ni, and V. In conditional logistic regression models, concentrations of Hg, Al, Ni, and V were significantly associated with the risk of HDP (p-FDR < 0.05). Compared to the lowest tertiles, the ORs (95% CI) for the highest tertiles of these four metals were 2.67 (1.44, 4.95), 3.09 (1.70, 5.64), 5.31 (2.68, 10.53), and 4.52 (2.26, 9.01), respectively. In the BKMR analysis, we observed a linear positive association between Hg, Al, V, and HDP, and a nonlinear relationship between Ni and HDP. A potential interaction between Al and V was also identified. We found that exposure to metal mixtures in early pregnancy, both individually and as a mixture, was associated with the risk of HDP. Potential interaction effects of Al and V on the risk of HDP may exist.

Air pollution and lung function in children

In this narrative review, we summarize the literature and provide updates on recent studies of air pollution exposures and child lung function and lung function growth. We include exposures to outdoor air pollutants that are monitored and regulated through air quality standards, and air pollutants that are not routinely monitored or directly regulated, including wildfires, indoor biomass and coal burning, gas and wood stove use, and volatile organic compounds. Included is a more systematic review of the recent literature on long-term air pollution and child lung function because this is an indicator of future adult respiratory health and exposure assessment tools have improved dramatically in recent years. We present "summary observations" and "knowledge gaps." We end by discussing what is known about what can be done at the individual/household, local/regional, and national levels to overcome structural impediments, reduce air pollution exposures, and improve child lung function. We found a large literature on adverse air pollution effects on children's lung function level and growth; however, many questions remain. Important areas needing further research include whether early-life effects are fixed or reversible; and what are windows of increased susceptibility, long-term effects of repeated wildfire events, and effects of air quality interventions.

Ambient Particle Components and Newborn Blood Pressure in Project Viva

Background

Both elemental metals and particulate air pollution have been reported to influence adult blood pressure (BP). The aim of this study is to examine which elemental components of particle mass with diameter ≤2.5 μm (PM_2.5) are responsible for previously reported associations between PM_2.5 and neonatal BP.

Methods and Results

We studied 1131 mother‐infant pairs in Project Viva, a Boston‐area prebirth cohort. We measured systolic BP (SBP) and diastolic BP (DBP) at a mean age of 30 hours. We calculated average exposures during the 2 to 7 days before birth for the PM_2.5 components—aluminum, arsenic, bromine, sulfur, copper, iron, zinc, nickel, vanadium, titanium, magnesium, potassium, silicon, sodium, chlorine, calcium, and lead—measured at the Harvard supersite. Adjusting for covariates and PM_2.5, we applied regression models to examine associations between PM_2.5 components and median SBP and DBP, and used variable selection methods to select which components were more strongly associated with each BP outcome. We found consistent results with higher nickel associated with significantly higher SBP and DBP, and higher zinc associated with lower SBP and DBP. For an interquartile range increase in the log Z score (1.4) of nickel, we found a 1.78 mm Hg (95% CI, 0.72–2.84) increase in SBP and a 1.30 (95% CI, 0.54–2.06) increase in DBP. Increased zinc (interquartile range log Z score 1.2) was associated with decreased SBP (−1.29 mm Hg; 95% CI, −2.09 to −0.50) and DBP (−0.85 mm Hg; 95% CI: −1.42 to −0.29).

Conclusions

Our findings suggest that prenatal exposures to particulate matter components, and particularly nickel, may increase newborn BP.